The present invention relates to an image forming apparatus.
In a conventional image forming apparatus such as a printer, a copier, a fax machine, and a multifunction product thereof, a toner image is formed according to an image. Then, the toner image is transferred to a sheet, and is fixed to the sheet through heating and pressing the sheet.
In the conventional image forming apparatus, a heat source may not be disposed in a pressing roller of a fixing device for reducing power consumption of a printer or a cost thereof. In such a printer, when a print command is received, a fixing roller and the pressing roller rotate for a specific period of time for warming up. Afterward, a temperature of the fixing roller is detected to confirm whether the detected temperature is within a specific range capable of fixing or a fixing enable temperature range. When it is confirmed that the temperature of the fixing roller is within the fixing enable temperature range, an operation of forming an image or a printing operation is started (refer to Patent Reference).    Patent Reference: Japanese Patent Publication No. 07-219386
In the conventional printer, when the printing operation described above is performed, it is difficult to obtain high print throughput representing throughput of forming an image. Accordingly, a time for warming up needs to be shortened, or the printing operation may be performed without warming up. In this case, after the printing operation is started, a problem such as cold offset may occur in the fixing device, thereby lowering image quality.
In the view of the problems described above, an object of the present invention is to provide an image forming apparatus capable of solving the problems of the conventional printer. In the image forming apparatus, it is possible to obtain high print throughput and improve image quality.
Further objects and advantages of the invention will be apparent from the following description of the invention.